Hi Nick,
Quote:
Originally Posted by Wavytone
Les the two I’ve looked through were both Mewlon 250 with thin vanes. As with Newtonians they are not the tool of choice for close double stars.
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I concede an unobstructed telescope is best of all for this application but given nearly all telescopes sold or made (commercial or home-made bespoke telescopes) today do have a central obstruction (apart from refractors) , can you explain why a Newtonian is not a "tool of choice" for close double stars ?
I repeat my earlier specific question regarding the Mewlon's failure to split a pair with 0.6" separation, were you viewing with the Mewlon 210 or the 250? Can you supply the id of the pair you were observing?
Please note my earlier posted observation (above) of splitting Gamma Sextantis (0.54 arc seconds at the time) with 25cm Newtonian at x580:"Well split with a dark hairs breadth between. Clearly split 90 - 95% of the time. In PA 70, diffraction rings surrounding both components virtually stationary. Another faint star 1' away magnitude11 in PA 340. "
Best,
L.